June 07, 2009

A model city: Chicago displayed in miniature; CAF shows a scale model of the Loop and nearby areas

Chicago, often seen as the model of growth for a 20th Century urban
industrial megalopolis, now has been reproduced in an enormous model
with the help of computers and a new three-dimensional "printing"
process called stereolithography.

Beginning this week, a 25- by-35-foot model of the city will be open
for viewing, free of charge at the Chicago Architecture Foundation,
inspired by similar models in Beijing and Shanghai that show how those
cities also have rapidly grown and changed.

The display portrays more than four square miles of the city, from the
lakefront on the east to Halsted Street on the west and Oak Street on
the north to 16th Street to the south. It contains an exact model of
every building in the area. There are more than 1,000 of them, from a
3-foot-high Sears Tower down to old two-story storefronts.

"We're not aware of any city model that has a footprint of this size
and scale anywhere else in this country," said Cathy Tinker, owner of
Columbian Model Works and Exhibit, whose employees have been
painstakingly installing the display in the atrium of the Santa Fe
Building, 224 S. Michigan Ave., the foundation's headquarters.

The exhibit fills the atrium, accompanied by other displays and
interactive exhibits that explore how the city was built, its
transportation networks, the impact of urbanization and urban renewal.

Foundation Vice President Gregory Dreicer credited the idea to Mayor
Richard Daley, who was intrigued by similar large-scale city models he
saw in Beijing and Shanghai. He said the mayor urged the foundation to
build one for Chicago.

The model buildings came from Columbian's workshop. The exhibit is
broken down into 400 city blocks, in squares the size of dinner plates
carried in food caterer's serving carts. With the buildings already
glued in place, the blocks were placed into the exhibit like waiters
carefully placing food plates into a buffet table.

Dreicer said the first step in the process was creating a digitized
three-dimensional computer model of the city that could be manipulated
on a screen. The designers did it using architectural drawings or
drawings purchased from commercial firms that collect such information.

To make each building, they went to firms that use the
three-dimensional printing process called stereolithography, used to
make design prototypes of various products like plastic containers for
food, cleaning or pharmaceutical products.

In that process, the digitized design specifications are fed into a
machine that controls a laser beam shot into a vat of acrylic resin.
The laser sculpts the object to the exact design specifications,
building it up and hardening it in layers thinner than a human hair,
with the "buildings" gradually rising from the resin, translucent but
in finished form.

"A building could take as much as 70 hours to be printed," said John
Welin, a senior designer at Columbian. "A smaller, older skyscraper
like Tribune Tower took about 40 hours."

The exhibit will run from Wednesday through Sept. 20. Ultimately, the
foundation plans to permanently display the exhibit, changing as
buildings come and go.

Wouldn't it have cooler to have done it as a giant holographic image? That way they could update it in real time, or at least daily. Get those scaffolds on the map. What's the CAF model have for the Sullivan facades recently uncovered on Wabash?

mgh, the Queens Museum model is a massing model instead of a true model of the city. There are some specific buildings recreated in it, but most are simply rough representations of what might be in that place.